A word appearing as fas (fass-) in the Declension of Nouns (DN) from the early 1930s glossed “fringe, border” (PE21/19) and “fringe” (PE21/26). ᴱQ. fas “tassel” also appeared in Qenya Lexicon of the 1910s, but there its stem form was fats- (QL/37), and in the contemporaneous Gnomish Lexicon its form was fatse (GL/34). Based on its Gnomish cognate fath (GL/34), its 1910s root was probably something like ✱ᴱ√FAÞA.
Neo-Quenya: I would use this word as “fringe, tassel”, but only as “border” in the sense of a tasseled border for cloth, for which I would probably use the more elaborate form ᴺQ. fassalë instead. I would also assume a derivation from the 1930s root ᴹ√PHAS having to do with shaggy or tangled hair (Ety/PHAS).
A verb in The Etymologies of the 1930s glossed “tangle” derived from the root ᴹ√PHAS (Ety/PHAS).